Like everyone else, I, too, have several locations that bring 'warm and fuzzies' to mind, but I have to say the FIRST time I know 'I've arrived' is after I've gone through all the gauntlets of bag check, ferry ride, then ticket booth at MK that I finally KNOW I'm in the park and only have to concern myself with the activities of the day!
That, and ESPECIALLY when I have my first cup of Joffrey's coffee in hand before we get on the ferry to cross over to MK and see the smiles on my families face when they, too, have THEIR cups in hand. THAT'S when I know I've arrived! :-D